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arXiv · 1405.4135

Construction of spin models displaying quantum criticality from quantum field theory

Ivan Glasser·J. Ignacio Cirac·Germán Sierra·Anne E. B. Nielsen
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Abstract

We provide a method for constructing finite temperature states of one-dimensional spin chains displaying quantum criticality. These models are constructed using correlators of products of quantum fields and have an analytical purification. Their properties can be investigated by Monte-Carlo simulations, which enable us to study the low-temperature phase diagram and to show that it displays a region of quantum criticality. The mixed states obtained are shown to be close to the thermal state of a simple nearest neighbour Hamiltonian.

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Ivan Glasser, J. Ignacio Cirac, Germán Sierra, Anne E. B. Nielsen. 2014-07-23. Construction of spin models displaying quantum criticality from quantum field theory. https://doi.org/10.1016/j.nuclphysb.2014.06.016

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